{"paper":{"title":"Transition-Potential Coupled Cluster","license":"","headline":"Transition-potential reference orbitals remove the dominant relaxation error from core-hole spectra calculations at EOM-CCSD cost.","cross_cats":[],"primary_cat":"physics.chem-ph","authors_text":"Devin A. Matthews, Megan E. Simons","submitted_at":"2020-11-06T21:02:25Z","abstract_excerpt":"The problem of orbital relaxation in computational core-hole spectroscopies, including x-ray absorption and x-ray photoionization, has long plagued linear response approaches, including equation-of-motion coupled cluster with singles and doubles (EOM-CCSD). Instead of addressing this problem by including additional electron correlation, we propose an explicit treatment of orbital relaxation via the use of \"transition potential\" reference orbitals, leading to a transition-potential coupled cluster (TP-CC) family of methods. One member of this family in particular, TP-CCSD(1/2), is found to esse"},"claims":{"count":4,"items":[{"kind":"strongest_claim","text":"TP-CCSD(1/2) essentially eliminates the orbital relaxation error and achieves the same level of accuracy for core-hole spectra as is typically expected of EOM-CCSD in the valence region.","source":"verdict.strongest_claim","status":"machine_extracted","claim_id":"C1","attestation":"unclaimed"},{"kind":"weakest_assumption","text":"That the transition-potential reference orbitals chosen with a 1/2 core-hole occupation are sufficient to capture the dominant relaxation effects across the tested first-row molecules without needing further correlation or orbital optimization.","source":"verdict.weakest_assumption","status":"machine_extracted","claim_id":"C2","attestation":"unclaimed"},{"kind":"one_line_summary","text":"TP-CCSD(1/2) removes orbital relaxation error in core-hole spectra by using half-electron transition-potential reference orbitals, delivering valence-region accuracy for x-ray absorption at EOM-CCSD cost.","source":"verdict.one_line_summary","status":"machine_extracted","claim_id":"C3","attestation":"unclaimed"},{"kind":"headline","text":"Transition-potential reference orbitals remove the dominant relaxation error from core-hole spectra calculations at EOM-CCSD cost.","source":"verdict.pith_extraction.headline","status":"machine_extracted","claim_id":"C4","attestation":"unclaimed"}],"snapshot_sha256":"7e61dd7e7a5630db93998880c52f8b829814ddf036e7c805fdf7b975f51066b0"},"source":{"id":"2011.03595","kind":"arxiv","version":1},"verdict":{"id":"629becba-9711-4ee1-8f5a-97ba0b2aa1ec","model_set":{"reader":"grok-4.3"},"created_at":"2026-05-14T22:01:31.762455Z","strongest_claim":"TP-CCSD(1/2) essentially eliminates the orbital relaxation error and achieves the same level of accuracy for core-hole spectra as is typically expected of EOM-CCSD in the valence region.","one_line_summary":"TP-CCSD(1/2) removes orbital relaxation error in core-hole spectra by using half-electron transition-potential reference orbitals, delivering valence-region accuracy for x-ray absorption at EOM-CCSD cost.","pipeline_version":"pith-pipeline@v0.9.0","weakest_assumption":"That the transition-potential reference orbitals chosen with a 1/2 core-hole occupation are sufficient to capture the dominant relaxation effects across the tested first-row molecules without needing further correlation or orbital optimization.","pith_extraction_headline":"Transition-potential reference orbitals remove the dominant relaxation error from core-hole spectra calculations at EOM-CCSD cost."},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":2,"snapshot_sha256":"c17d1f8299605111b9d8ec2ca4cba519356f8818fb5e7cfa2b3b8b4ad262acf2"},"author_claims":{"count":1,"strong_count":1,"snapshot_sha256":"5e3b23b793a24ad44d50f012bed3c12f7c9e9c566d826ad85b79440943422c6c"},"builder_version":"pith-number-builder-2026-05-17-v1"}